Extracted from Pike v7.3 release 16 at 2002-03-05.
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GL

Method GL.glPixelZoom()


Method glPixelZoom

void GL.glPixelZoom(float xfactor, float yfactor)

Description

GL.glPixelZoom specifies values for the x and y zoom factors. During the execution of GL.glDrawPixels or GL.glCopyPixels, if (xr , yr ) is the current raster position, and a given element is in the mth row and nth column of the pixel rectangle, then pixels whose centers are in the rectangle with corners at .sp .ce (xr ~+~ n cdot "xfactor", yr ~+~ m cdot "yfactor") .sp .ce (xr ~+~ (n+1) cdot "xfactor", yr ~+~ (m+1) cdot "yfactor") .sp are candidates for replacement. Any pixel whose center lies on the bottom or left edge of this rectangular region is also modified.

Pixel zoom factors are not limited to positive values. Negative zoom factors reflect the resulting image about the current raster position.

Parameter xfactor

Specify the x and y zoom factors for pixel write operations.

Throws

GL_INVALID_OPERATION is generated if GL.glPixelZoom is executed between the execution of GL.glBegin and the corresponding execution of GL.glEnd.